I'd be interested to hear other people's observations/opinions on this stuff, and, what kind of setup they have.
I have suffered with GDA for as long as I can remember, always on day 3-4 it would appear then get worse by day 6-7. Personally I put it down to an overdose of some micro element (zinc, manganese??) - at least in my setup.
Tank: 150L
Light: 140w high intensity full spectrum PAR LED's
Substrate: Westland aquatic compost capped with 4" sand
Photoperiod: 2hr low intensity, 6 hour high, 2 hour low
Co2: Pressurised CO2
Ferts: Full EI
GH 7
KH 5
Water 50/50 RO/tap
Weekly 50% WC
I recently (about three/four weeks now) have stopped dosing micros and iron altogether. I figured I'll keep on with the macro as per EI & add a little Mg (about 5ppm at water change and a few ppm throughout the week since we're a bit low in the tap in London, especially as I'm cutting the water) and see how the substrate can maintain the plants.
Well, in the process the GDA has gone I've not had it for a couple of weeks now, the week just gone being the best week yet - I hadn't actually noticed I'm not constantly cleaning the glass anymore. The plants are picking up in health too. I think I underestimated the substrate as it appears dosing any form of iron or micro nutrient (bar magnesium) really causes me massive plant health issues with the included bonus of GDA.
This was literally the ONLY algae I was suffering with while all the changes I listed further below were carried out. CO2, light and flow/filtration remained the same all the way through.
Not trying to say anything about toxicity or take any sides in the debate on what actually GDA is. I just want to know what people who have successfully got rid of it changed at the time.
Some further observations:
Before reducing trace and iron, I tried everything else over the years...
Starving macros
Overdosing macros
doubling trace
trebling potassium
decreasing magnesium
increasing magnesium (interestingly this aggravated the situation ten fold)
reconstituting RO/DI (while I was doing this, the GDA would show up on day 6-7 with the same dosing routines, never earlier)
Using commercial liquid fert (profito) (again, an observation here was that the GDA showed up later when dosing this instead of the chelated trace mix)
Not sure why I never tried cutting the micros out (and foolishly even increasing them!) I was always under the impression the tap was light on that sort of thing, that and the evidently potent substrate I have in there. I didn't have the patience or the bottle to leave it a few weeks. I'd always add some micro by day 2-3.
Really would like to hear what others have experienced.
I have suffered with GDA for as long as I can remember, always on day 3-4 it would appear then get worse by day 6-7. Personally I put it down to an overdose of some micro element (zinc, manganese??) - at least in my setup.
Tank: 150L
Light: 140w high intensity full spectrum PAR LED's
Substrate: Westland aquatic compost capped with 4" sand
Photoperiod: 2hr low intensity, 6 hour high, 2 hour low
Co2: Pressurised CO2
Ferts: Full EI
GH 7
KH 5
Water 50/50 RO/tap
Weekly 50% WC
I recently (about three/four weeks now) have stopped dosing micros and iron altogether. I figured I'll keep on with the macro as per EI & add a little Mg (about 5ppm at water change and a few ppm throughout the week since we're a bit low in the tap in London, especially as I'm cutting the water) and see how the substrate can maintain the plants.
Well, in the process the GDA has gone I've not had it for a couple of weeks now, the week just gone being the best week yet - I hadn't actually noticed I'm not constantly cleaning the glass anymore. The plants are picking up in health too. I think I underestimated the substrate as it appears dosing any form of iron or micro nutrient (bar magnesium) really causes me massive plant health issues with the included bonus of GDA.
This was literally the ONLY algae I was suffering with while all the changes I listed further below were carried out. CO2, light and flow/filtration remained the same all the way through.
Not trying to say anything about toxicity or take any sides in the debate on what actually GDA is. I just want to know what people who have successfully got rid of it changed at the time.
Some further observations:
Before reducing trace and iron, I tried everything else over the years...
Starving macros
Overdosing macros
doubling trace
trebling potassium
decreasing magnesium
increasing magnesium (interestingly this aggravated the situation ten fold)
reconstituting RO/DI (while I was doing this, the GDA would show up on day 6-7 with the same dosing routines, never earlier)
Using commercial liquid fert (profito) (again, an observation here was that the GDA showed up later when dosing this instead of the chelated trace mix)
Not sure why I never tried cutting the micros out (and foolishly even increasing them!) I was always under the impression the tap was light on that sort of thing, that and the evidently potent substrate I have in there. I didn't have the patience or the bottle to leave it a few weeks. I'd always add some micro by day 2-3.
Really would like to hear what others have experienced.
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